Question from the young and inexperienced

Hey guys,
I’ve grown up working on cars, and I’m studying electrical engineering, but I’m a total newbie when it comes to putting the two together in an electric car.

Here’s my first question: What is a Contactor, what is it used for? Is it basically a giant relay?

Thanks.

You are correct, just a big relay

Is it used for reversing the polarity of the power to the motor, or is it just a “main-switch”?

It can be both…